Air Rights: What They Are and How Much You Own

Air rights are the right to use and build in the space above a piece of land. They normally belong to the landowner, but zoning limits how much can be built, and the public has a right of transit through navigable airspace. In cities, "air rights" often means a lot's unused development rights, which some codes let an owner transfer.

This guide is written by Pillar, a land research platform. Its sources are court opinions, statutes, FAA rules and local planning agencies, each linked and read on November 14, 2026. It is general information, not legal advice. The law differs by state and city, so confirm anything that matters with a licensed attorney or surveyor in your state.

What are air rights?

The phrase covers two different things.

The space above the land. California's Civil Code, for example, defines land to include "free or occupied space for an indefinite distance upwards as well as downwards, subject to limitations upon the use of airspace imposed, and rights in the use of airspace granted, by law."

Unused development rights. New York City's Department of City Planning zoning glossary says that when a building's floor area is less than the maximum permitted on its zoning lot, the difference is its unused development rights, and that "Unused development rights are often described as air rights."

Three things limit both kinds:

• Zoning. Height limits and floor area ratios cap what can be built.
• Navigable airspace. Federal law gives citizens a public right of transit through it.
• Recorded documents. Easements, covenants and earlier transfers of development rights.

How much airspace do you own above your property?

Federal law sets no fixed height. The leading case is United States v. Causby, decided by the U.S. Supreme Court in 1946.

The Causbys owned a house and chicken farm on 2.8 acres near an airport outside Greensboro, North Carolina. Military aircraft used a glide path that passed over the property at 83 feet, which was 67 feet above the house. The noise made them give up the chicken business.

The Court said three things:

• Ownership does not run up without limit. The old doctrine that it did "has no place in the modern world. The air is a public highway, as Congress has declared."
• The owner controls the space near the ground. "The landowner owns at least as much of the space above the ground as he can occupy or use in connection with the land." That holds even where nothing is built: "The fact that he does not occupy it in a physical sense—by the erection of buildings and the like—is not material."
• Only some overflights take property. "Flights over private land are not a taking, unless they are so low and so frequent as to be a direct and immediate interference with the enjoyment and use of the land."

The Court agreed that the flights had imposed a servitude on the land, a taking that required compensation. It then sent the case back because the lower court's findings did not describe the easement precisely. It set no height: "The airspace, apart from the immediate reaches above the land, is part of the public domain. We need not determine at this time what those precise limits are."

The federal statute. 49 U.S.C. 40103 says "The United States Government has exclusive sovereignty of airspace of the United States" and "A citizen of the United States has a public right of transit through the navigable airspace." Section 40102 defines navigable airspace as "airspace above the minimum altitudes of flight prescribed by regulations under this subpart and subpart III of this part, including airspace needed to ensure safety in the takeoff and landing of aircraft."

The minimum altitudes. The FAA's general rule is 14 CFR 91.119. Except when necessary for takeoff or landing, it sets these minimums:

• Anywhere. An altitude that allows an emergency landing without undue hazard to persons or property on the surface if a power unit fails.
• Congested areas. Over any congested area of a city, town or settlement, or over any open air assembly of persons, 1,000 feet above the highest obstacle within a horizontal radius of 2,000 feet of the aircraft.
• Other areas. 500 feet above the surface, except over open water or sparsely populated areas. There the aircraft may not be operated closer than 500 feet to any person, vessel, vehicle or structure.
• Helicopters, powered parachutes and weight-shift-control aircraft. If the operation is conducted without hazard to persons or property on the surface, a helicopter may be operated below the congested-area and other-area minimums, provided each person operating it complies with any routes or altitudes the FAA specifically prescribes for helicopters. A powered parachute or weight-shift-control aircraft may also be operated below the other-area minimum if the operation is conducted without hazard to persons or property on the surface.

As we read these sources, the altitudes are flight rules, not a property line. In Griggs v. Allegheny County (1962), the Court held that the county that owned an airport had taken an air easement over a home under the flight path and had to pay just compensation.

Can a drone fly over my property?

Under federal rules, usually yes. The FAA's page What To Know About Drones says "You can fly drones in most locations below 400 feet" and "The FAA does not regulate privacy, but local privacy laws may apply to drone operations." State trespass and privacy laws differ.

What the FAA regulates. A 2023 FAA fact sheet says the FAA "has the exclusive authority to regulate aviation safety and the efficient use of the airspace by aircraft" and that this framework applies fully to drones. The small drone rule, 14 CFR 107.51, caps altitude at 400 feet above ground level, unless the drone is flown within a 400-foot radius of a structure and no higher than 400 feet above the structure's immediate uppermost limit. That is a ceiling: the fact sheet says the FAA has not set minimum altitudes for drones.

What states can regulate. The fact sheet says laws on land use or zoning, privacy and trespass on property would likely not be preempted, if they are aimed at objectives other than aviation safety or airspace efficiency and do not impair the reasonable use of the airspace by drones. Two statutes show how far the answers differ:

• Nevada. NRS 493.103 lets a person who owns or lawfully occupies real property bring a trespass action against the owner or operator of a drone flown less than 250 feet over it. The drone's owner or operator must have flown it over the property below 250 feet on at least one previous occasion, and the owner or occupant must have notified the drone's owner or operator that the flight was not authorized. Subsection 2 lists four exceptions: a drone lawfully in the flight path for landing at an airport, airfield or runway; a drone in the process of taking off or landing; lawful operation by a law enforcement agency in accordance with NRS 493.112 or by a public agency in accordance with NRS 493.115; and lawful operation by a business registered in Nevada or by a land surveyor. The business and surveyor exception applies only if the operator is licensed or otherwise approved by the FAA to operate the drone, the drone is operated within the scope of the lawful activities of the business or surveyor, and the operation does not unreasonably interfere with the existing use of the property.
• Oregon. ORS 837.380 sets no height. A person who owns or lawfully occupies real property may sue the operator of a drone flown over it if the operator has flown a drone over the property on at least one previous occasion and the person notified the owner or operator that they did not want it flown there. No action lies if the drone is lawfully in the flight path for landing at an airport, airfield or runway and is taking off or landing, or if it is operated for commercial purposes in compliance with FAA authorization.

Don't shoot at it. The FAA page says it is illegal under federal law to shoot at an aircraft, unmanned aircraft included, and that doing so "could result in a civil penalty from the FAA and/or criminal charges from federal, state or local law enforcement."

How are air rights sold? Unused floor area in New York City

Where a code allows it, selling air rights means moving unused floor area from one lot to another. New York City publishes its rules in detail, so we use it as the example. These rules apply only there. The city's glossary defines floor area ratio (FAR) as the ratio of total building floor area to the area of its zoning lot. A district's FAR times the lot area gives the maximum floor area allowed.

Zoning lot merger. The glossary says "A zoning lot merger is the joining of two or more adjacent zoning lots into one new zoning lot." It says a merger lets unused development rights shift from one lot to another as-of-right. Paragraph (d) of the "zoning lot" definition in Section 12-10 of the Zoning Resolution covers a tract of two or more lots of record that are contiguous for a minimum of 10 linear feet, located within a single block and declared to be one zoning lot. The declaration is made at the time of filing for a building permit, or for a certificate of occupancy if no permit is required. Each party in interest, as paragraph (f)(4) of the definition defines that term, must sign the declaration or execute a written waiver of its right to sign, recorded at or before the declaration is recorded. The declaration and each waiver are recorded against each lot of record the declaration covers. Before it issues the permit or certificate of occupancy, the Department of Buildings must be given a certificate from a title insurance company licensed in New York State showing that each party in interest has signed the declaration or waived, and that the declaration and waivers are recorded. Where the city is a fee owner, the New York City Law Department may issue that certificate.

Transfers from landmarks. Section 75-422, last amended December 5, 2024, has the Chairperson of the City Planning Commission allow, by certification, a transfer from a lot containing a designated landmark to receiving lots within the "surrounding area." Portions of lots used for cemetery purposes, statues, monuments or bridges are excluded. Section 75-421 defines the surrounding area as all zoning lots on the landmark's block and all zoning lots across a street or street intersection from the block. In commercial districts where the maximum FAR for commercial uses is 15.0 or greater, it also covers zoning lots that, except for the intervention of streets or street intersections, form a series extending to the landmark's zoning lot. All such lots must be in the same ownership, meaning fee ownership or the alternative ownership arrangements of the zoning lot definition in Section 12-10. The conditions of a transfer include:

• How much can leave. The maximum floor area the district allows, not counting bonuses, less the floor area of all existing buildings on the landmark lot and any floor area already transferred.
• How much a lot can receive. The increase can't exceed the maximum floor area allowable on the receiving lot by more than 20 percent. The limit is 30 percent in commercial or manufacturing districts where the maximum FAR for non-residential uses is 15.0 or greater, and a transfer above 30 percent in those districts needs a special permit under Section 74-79.
• It is permanent. "Each transfer, once completed, shall irrevocably reduce the amount of floor area that may be developed or enlarged on the granting lot by the amount of floor area transferred."
• It is recorded. The owners file notice of the restrictions on both lots in the Office of the Register of the City of New York.

The glossary PDF is dated 2021 and describes landmark transfers as made by City Planning Commission special permit, so rely on the current text of the Zoning Resolution.

How to calculate unused development rights: a worked example

This is an illustration with made-up numbers, using the New York City rules quoted above.

1. Lot area. Lot A is 10,000 square feet.
2. Permitted floor area. Its district has a maximum FAR of 4.0. 10,000 × 4.0 = 40,000 square feet.
3. Existing building. The building on Lot A has 22,000 square feet of floor area, measured the way the code defines floor area.
4. Unused development rights. 40,000 − 22,000 = 18,000 square feet. If floor area had already been transferred off the lot, you would subtract that too. Here it is zero.

What happens to the 18,000 square feet depends on the route:

• By merger. Lot B next door is vacant, also 10,000 square feet, with the same FAR. Merged, the new zoning lot is 20,000 square feet and allows 80,000 square feet of floor area. With 22,000 built, 58,000 remains: Lot B's own 40,000 plus the 18,000 shifted from Lot A.
• By landmark transfer. Suppose instead that Lot A holds a designated landmark and Lot C across the street may build 40,000 square feet. Under the 20 percent limit, Lot C can receive 8,000 square feet. The other 10,000 needs another receiving lot in the surrounding area or stays unused.

Only the local code decides what can transfer. Another city's FAR, eligible lots and approvals can all differ, and its code may offer no transfer route. Have a zoning attorney or architect run the numbers on the real lot.

What are transferable development rights (TDR)?

A TDR program lets an owner separate development rights from a "sending" site and sell them for use on a "receiving" site. New York City's glossary says a TDR allows a transfer between zoning lots "in limited circumstances, usually to promote the preservation of historic buildings, open space or unique cultural resources." Two counties use the idea to protect rural land.

• King County, Washington. Under the county's program, sending sites are "rural or resource lands with farm, forest, open space, or regional trail amenities, and in some cases, urban land with conservation values." When an owner separates some or all of the development rights, the property is conserved through a permanent conservation easement and stays in private ownership.
• Montgomery County, Maryland. The county's Office of Agriculture says its Agricultural Reserve zone "sets a 25-acre subdivision density but allows landowners to sell development rights to areas designated for growth elsewhere in the County, based on the previous zoning designation of 1 unit per 5 acres." Under Section 4.2.1 of the zoning ordinance, the transfer must be recorded in the county land records. The county says the TDR easement permanently limits the property to 1 unit per 25 acres, regardless of future zoning changes in the Agricultural Reserve.

A sending parcel in either program carries a permanent easement, so acreage and zoning alone do not tell you what can be built on it.

How much are air rights worth? The worked example above gives a quantity of floor area and no price. King County's TDR Marketplace page says TDR prices "will vary depending on the amount of development capacity each TDR provides a developer" and that its market "is driven by supply and demand." The county's program offers sales data and market activity for its TDR transactions. That data covers King County's program, so it does not price floor area in New York City.

Building in airspace: over highways and in condominiums

Over a highway. Massachusetts General Laws chapter 6C, section 46 lets the Massachusetts Department of Transportation lease air rights over land it owns or holds in connection with the turnpike and the Boston extension for terms not to exceed 99 years. A lease of 40 years or more needs the governor's approval. Before it leases air rights in a particular location, the department must find that the construction and use of what is built under the lease will be in no way detrimental to the maintenance, use and operation of the turnpike or the metropolitan highway system. In Boston it must also find, after consultation with the mayor, that the construction and use will "preserve and increase the amenities of the community." Construction and occupancy stay subject to the building, fire, garage, health and zoning laws and local rules that apply in the city or town. In January 2015 the department and the MBTA announced a developer for Turnpike Air Rights Parcel 13 in Boston, "approximately 54,500 square feet of air rights over the Massachusetts Turnpike and portions of the MBTA Green Line tunnel across the street from the Hynes Convention Center." The project still needed state and municipal permits at that point, and we did not check its later status.

As a unit of real property. California's Civil Code section 4125 says a condominium consists of "an undivided interest in common in a portion of real property coupled with a separate interest in space called a unit," with boundaries described on a recorded final map, parcel map or condominium plan. The area within those boundaries "may be filled with air, earth, water, or fixtures, or any combination thereof, and need not be physically attached to land except by easements for access and, if necessary, support."

Do you have a right to light, air or a view?

It depends on state law and the facts. The two cases below came out differently.

A Florida case shows one answer: Fontainebleau Hotel Corp. v. Forty-Five Twenty-Five, Inc., decided by the state's Third District Court of Appeal in 1959. The Fontainebleau in Miami Beach was building a fourteen-story addition. In winter its afternoon shadow would extend over the cabana, swimming pool and sunbathing areas of the Eden Roc next door. The court found "no legal right to the free flow of light and air from the adjoining land," and reversed the injunction with directions to dismiss the complaint. It said no American decision had been cited in which a landowner without "some contractual or statutory obligation" to rely on had a legal right to the free flow of light and air across a neighbor's land.

Wisconsin's Supreme Court took a different view in Prah v. Maretti (1982). It held that private nuisance law applied to a claim that a neighbor's planned house would shade rooftop solar collectors, without deciding whether the owner was entitled to relief.

Florida's solar easement statute shows what a written right looks like. Easements obtained to maintain exposure of a solar energy device "shall be created in writing and shall be subject to being recorded and indexed in the same manner as any other instrument affecting the title to real property."

If a view or sunlight is part of what you are paying for, look for a recorded easement or covenant that protects it. Our guide to deed restrictions explains how to find recorded covenants.

Air rights when you buy or develop land

Check five things before you make an offer.

1. Height and floor area in the zoning code. The height limit, the floor area ratio or lot coverage, and the setbacks decide how much of the airspace you can fill. Our R1 zoning guide compares those standards across ten codes. Confirm you are reading the zoning district and not the plan designation; see zoning vs. future land use. In a planned unit development, the approved plan may set the rules instead of the base district.

2. Whether development rights have already left the parcel. A zoning lot declaration, a TDR easement or a conservation easement is a recorded document. Ask the title company for every recorded easement, declaration and covenant, and read the exceptions in the title commitment.

3. Avigation easements. FAA guidance for airports that buy land with federal grants, Advisory Circular 150/5100-17, says "An avigation easement is a conveyance of airspace over another property for use by the airport." The rights typically include the right of flight, the right to cause noise and dust, and the right to remove objects protruding into the airspace and prohibit future obstructions. The circular says the easement must run with the land, so it restricts later owners. An ALTA survey shows the location, width and recording information of every plottable easement in the documents the surveyor is given or obtains, with a note where an easement can't be located from its document or is a blanket easement.

4. Airport zoning. Florida's section 333.03 says every political subdivision with an airport hazard area inside its limits "shall adopt, administer, and enforce" airport protection zoning regulations for that area. Look for an airport overlay on the zoning map and read its height limits.

5. FAA notice of proposed construction. Under 14 CFR 77.9, you must file notice with the FAA if the FAA requests it or if you propose:

• Any construction or alteration that is more than 200 feet above ground level at its site.
• Any construction or alteration that exceeds an imaginary surface extending outward and upward at one of three slopes. The first is 100 to 1 for a horizontal distance of 20,000 feet from the nearest point of the nearest runway of a listed airport whose longest runway is more than 3,200 feet in actual length. The second is 50 to 1 for 10,000 feet from the nearest point of the nearest runway of a listed airport whose longest runway is no more than 3,200 feet. The third is 25 to 1 for 5,000 feet from the nearest point of the nearest landing and takeoff area of a listed heliport. The two runway slopes exclude heliports.
• Any highway, railroad or other traverse way for mobile objects whose height would exceed those standards once adjusted upward by the amount paragraph (c) sets for what travels on it, such as 23 feet for a railroad.
• Any construction or alteration on a listed airport or heliport.

"Listed" means paragraph (d): a public use airport in the Airport/Facility Directory, Alaska Supplement or Pacific Chart Supplement; a military airport under construction, or an airport under construction that will be available for public use; an airport operated by a federal agency or the Department of Defense; and an airport or heliport with at least one FAA-approved instrument approach procedure. Paragraph (e) lists construction that needs no notice.

As we read the slopes, 100 to 1 means 1 foot of height for every 100 feet of distance, so a building near a runway can need notice at far less than 200 feet.

If notice is required, Section 77.7 requires FAA Form 7460-1 at least 45 days before the start date of the proposed construction or alteration or the date an application for a construction permit is filed, whichever is earliest. If the proposal is also subject to Federal Communications Commission licensing, notice is due on or before the date the application is filed with the FCC. The 45-day requirement is waived "if immediate construction or alteration is required because of an emergency involving essential public services, public health, or public safety." In that case you may notify the FAA by any available, expeditious means, and you must file the completed form within 5 days of that initial notice.

Where Pillar fits

Pillar's map layers show zoning, floodplain, wetlands, utilities and future land use over parcel boundaries, which helps with a first look at a site's district. Coverage varies by dataset, and a map label is not the code or the title record.

Quick answers

What are air rights in real estate? The right to use and build in the space above a parcel. In cities the term often means unused development rights: floor area the zoning allows but the building has not used.

How much airspace do you own above your property? Federal law sets no fixed height. In Causby the Supreme Court said the owner has at least as much of the space above the ground as can be occupied or used in connection with the land.

Who owns the airspace above my house? You control the immediate reaches above your land. Federal statute gives the United States sovereignty of the airspace and citizens a public right of transit through navigable airspace.

Can a drone fly over my property? The FAA says you can fly drones in most locations below 400 feet. Some states give owners a claim after a prior flight and notice, such as Nevada below 250 feet, with exceptions.

Can you sell air rights? Only where the local code provides a way, such as a zoning lot merger or a transferable development rights program. New York City's routes include a zoning lot merger and, for a lot with a designated landmark, a transfer by certification under Section 75-422. Each has its own conditions.

Do I have a right to a view or sunlight? It depends on state law and the facts. A Florida court found no legal right to light and air from adjoining land, while Wisconsin's high court let a nuisance claim over sunlight blocked from solar collectors proceed.